I have found that if a game makes less than 100k in its fiscal year, the developer won’t need to buy a license. Does this include for purchased downloadable in-game content, such as story expansions and micro-transactions? And could those still be sold after the fiscal year has ended, or will i need to purchase a license?
It’s true that if you generate less than $100,000 USD in revenue you won’t be required to purchase a Plus license. However, it’s not necessarily tracked over a fiscal year, but rather the most recent 12 month period. This includes all revenue from your game development (ads, IAP, etc.) From the software terms:
The Financial Threshold for Unity Personal is US $100,000 for the most recent twelve (12) month period. To be Tier Eligible to use Unity Personal, your Total Finances may not exceed US $100,000.
So if any point you’re bringing in $100K+ in the most recent 12 months, you’ll want to get a Plus (or Pro) license. It’s $35/month, so if you’re at the point of generating $100,000+ I wouldn’t worry so much about staggering your income throughout the year to try and avoid getting a license.
Source: Unity License terms
Best of luck with your game development ٩(^ᴗ^)۶